Food slicing machine

ABSTRACT

A meat slicing machine has a base which supports an inclined rotary knife and a removable reciprocating carriage having an inclined material supporting surface extending parallel to the axis of the knife. The meat is advanced down the surface by a gripper having a plurality of depending prongs engaging the meat and supported by a pivotable arm slidably mounted on an inclined guide rod. The gripper and arm are fed by a follower engaging an inclined lead screw which is indexed during each return stroke of the carriage by oscillation of a one-way clutch having a finger extending for engagement with an adjustable stop mounted on the base.

United States Patent Inventor Richard S. Hartley Troy, Ohio Appl. No.8,231 Filed Feb. 3, 1970 Patented Oct. 19, 1971 Assignee The HobartManufacturing Company Troy, Ohio FOOD SLICING MACHINE 8 Claims, 7Drawing Figs.

U.S. Cl [46/ 102 L, 146/217 Int. Cl B2611 l/28, 826d 4/36, 826d 5/42Field of Search 146/ 102 R,

102 G, 102 L, 102 H,94 R, 217,113 D Primary ExaminerWillie G.Abercrombie Attorney-Marechal, Biebel, French & Bugg ABSTRACT: A meatslicing machine has a base which supports an inclined rotary knife and aremovable reciprocating carriage having an inclined material supportingsurface extending parallel to the axis of the knife. The meat isadvanced down the surface by a gripper having a plurality of dependingprongs engaging the meat and supported by a pivotable arm slidablymounted on an inclined guide rod. The gripper and arm are fed by afollower engaging an inclined lead screw which is indexed during eachreturn stroke of the carriage by oscillation of a one-way clutch havinga finger extending for engagement with an adjustable stop mounted on thebase.

FOOD sucmc MACHINE BACKGROUND OF THE INVENTION In one form of meatslicing machine, a cross feed meat plate is mounted on a carriage whichis reciprocated adjacent a rotary circular knife. The meat is secured tothe meat plate by a vertically movable clamping member, and the meatplate is positively advanced towards the knife in a step-by-step mannerby a cross feel mechanism, as for example, a cross feed screw mechanismsuch as disclosed in U.S. Pats. No. 1,284,684 and No. 1,626,902. Inanother form of slicing machine, such as disclosed in U.S. Pat. No.2,752,968, the meat is gripped by a plurality of hooks projecting from across feed carriage supported adjacent an inclined surface extendingfrom the path of an oscillating rotary knife.

Due to the complexity of the machines disclosed in the above patents andthe difficulty in cleaning them, the construction of meat slicers hastaken a more simplified form such as disclosed in US. Pat. No. 3,051,207which issued to the assignee of the present invention. This slicingmachine incorporates a reciprocating carriage having an inclined meatsupporting surface which extends upwardly from an adjustable gaugeplate. However, it has been found that when meat is sliced very thin orshredded on a gravity feed meat slicer such as shown in the latterpatent, it is difficult to obtain slices which have a precisely uniformthickness. For example, with some cooked meats, there is a tendency forthe meat to move upwardly on the meat supporting surface and away fromthe gauge plate causing the thickness of the slice to vary slightly.

SUMMARY OF THE INVENTION The present invention is directed to a gravityfeed slicing machine which incorporates an improved and simplified crossfeel mechanism especially adapted for converting meat into thin slicesof precisely uniform thickness. The slicing machine of the invention notonly provides a simplified structure which effects positive andprecisely controlled cross feed of the meat during each return stroke ofthe carriage, but also provides for convenient cleaning of the slicerincluding the cross feed mechanism.

In accordance with a preferred embodiment of the invention, a slicingmachine incorporates an inclined circular cutting knife and areciprocating carriage having a meat supporting surface extendingparallel to the axis of the knife. A meat gripper includes a pluralityof pointed prongs and is supported by an arm pivotally and slidablymounted on an inclined guide rod movable with the carriage and extendingparallel to the meat supporting surface. An inclined lead screw extendsbelow the guide rod in parallel spaced relation and is engaged by aretractable pin carried by a yoke member slidably mounted on the guiderod with the arm.

A one-way clutch is mounted on each end of the lead screw, and a fingerextends from the lower clutch for engaging a stop member during eachreturn stroke of the carriage. The stop member is supported by the baseof the slicing machine and is infinitely adjustable betweenpredetermined limits to control the degrees of rotation of the leadscrew during each return stroke of the carriage. An adjustable gaugeplate is supported adjacent the knife and is calibrated with thepositive cross feed of the meat gripper and the inclined meat supportingsurface of the carriage to assure that each slice has a preciselyuniform thickness.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of aslicing machine constructed in accordance with the invention;

FIG. 2 is a front elevational view of the slicing machine shown in FIG.11, with portions broken away;

FIG. 3 is a fragmentary section taken generally on the lines 33 of FIG.2;

FIG. 4 is an enlarged fragmentary section taken generally on the line 44of FIG. 3;

FIG. 5 is an enlarged section taken generally on the line 5- 5 of FIG.2;

FIG. 6 is a section taken generally on the line 6-6 of FIG. 4; and

FIG. 7 is a fragmentary section of the meat gripping member shown inFIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENT The slicing machine shown inFIG. 1 includes a rectangular hollow base which supports a housing 12having an upwardly projecting hollow portion for enclosing an electricmotor (not shown) connected by gears to drive a circular cutting knife15 inclined at an angle of approximately 45. One side of the knife 15 ispartially covered by a shroud l8 mounted on the housing portion 13 andthe other side of the knife 15 is partially covered by a guard plate 20removably secured to the shroud 18 by a thumb screw 21.

The housing 12 also includes an upwardly projecting longitudinallyextending portion 22 which encloses a pair of guide rods (not shown)extending parallel to the knife 15. A carriage 25 is mounted on a curvedsupport arm 26 which is secured to a slide member 27 slidably mounted onthe guide rods. The carriage 25 includes an L-shaped meat tray 30 (FIG.3) having a flat bottom wall 32 which is removably secured to the upperportion of the arm 26 by a wing screw 33. The bottom wall 32 defines amaterial or meat supporting surface 34 and is inclined in the oppositedirection from the knife 15 so that it extends parallel to therotational axis of the knife. The inclined bottom wall 32 of the meattray 30 adjoins a vertical wall 35, and a flange 36 (FIG. 3) and a boss37 project forwardly from the wall 35.

A handle 40 is secured to the arm 26 to provide for manuallyreciprocating the carriage through a feed stroke and a return stroke inrelation to the knife 15. The carriage 25 may also be reciprocated by aharmonic drive mechanism enclosed within the base 10 as disclosed in theabove Hartley US. Pat. No. 3,051,207. An inclined gauge plate 42 (FIGS.l and 2) is positioned parallel to the knife 15 and is supported by apair of parallel spaced inclined rods 43 which extend parallel to thebottom wall 32 of the meat tray 30 as disclosed in the above Hartleypatent. A calibrated dial 45 is mounted on a shaft (not shown) whichprojects through the front wall of the housing portion 22 and is rotatedto adjust infinitely the position of the gauge plate 42 betweenpredetermined limits in relation to the cutting edge of the knife 15.

In accordance with the present invention, a guide rod 48 (FIGS. 1 and 3)has its lower end supported by the boss 37 of the meat tray 30 and isinclined on the same angle as the bottom 'wall 32 of the meat tray 30. Apivotable arm 49 (FIGS. I and 3) is slidably mounted on the guide rod 48and supports a meat gripping member or gripper 50 which includes a bar52 pivotally connected to the arm 49 by a pin 53. A handle 55 is mountedon the pin 53, and a plurality of pointed prongs 56 depend from the bar52 in parallel spaced relation. Referring to FIG. 7, the meat gripper 50also includes a pair of end prongs 57 on each of which is mounted apointed tip 58 formed of a low friction plastic material. The plastictips 58 project below the points of the prong 56 and are adapted toengage the surface 34 of the meat tray 30 when the meat gripper 50 isreleased so that the pointed ends of the prongs 56 are protected and areprevented from scratching of the surface 34. An elongated inclined leadscrew is positioned below the guide rod 48 in parallel spaced relation,and the upper end portion of the lead screw 60 is rotatably supported bya bracket 62 secured to the upper end of the guide rod 48 by a screw 63.A bearing 64 (FIG. 4) rotatably supports the lower end of the lead screw60, and thus the lead screw 60 and the guide rod 48 are supported as acantilevered unit from the flange 36 and boss 37 of the tray 30.

A one-way clutch 65 is mounted on the lower end portion of the leadscrew 60 and includes a cam member 66 (FIG. 6) which is keyed to thelead screw and has a pair of diametrically opposed tapered cavities 67.A cylindrical sleeve or casing 68 surrounds the cam member 66 andconfines cylindrical rollers 69 within the cavities 67. A plate 71 (FIG.4) is secured to one end of the sleeve 68 and includes a downwardlyextending finger 72. A retaining ring 73 is secured to the opposite endof the casing 68, and a torsion coil spring 74 surrounds the bearing 64.The spring 74 has one end connected to the casing 68 and an opposite endconnected to the flange 36.

Another one-way clutch 80 is mounted on the upper end portion of thelead screw 60 adjacent the bracket 62 and includes a torsion coil spring82 which is wound on the lead screw 60 and has one end connected to thebracket 62. A sleeve 83 surrounds the torsion spring 82 and is confinedbetween the bracket 62 and a collar 84 secured to the lead screw. A yokeor follower member 86 (FIGS. 2 and includes parallel spaced ears 87which are slidably mounted on the guide rod 48 on opposite sides of thearm 49. A semicylindrical cavity 88 (FIG. 5) is formed within thefollower member 86 and receives the lead screw 60. A retractable pin 90is carried by the follower member 86 and has an inner end portion whichis urged into engagement with the thread of the lead screw 60 by acompression spring 92 enclosed within a bore extending from the cavity88. A cross pin 94 extends laterally from the pin 90 and is receivedwithin a slot 96 within the member 86 when the inner portion of theretractable pin 90 is in engagement with the lead screw 60.

When the pin 90 is retracted and is rotated a few degrees, the cross pin94 is out of alignment with the slot 96 and thereby prevents the pin 90from engaging the lead screw 60 so that the member 86, the arm 49 andthe gripper 50 are free to slide on the guide rod 48. A knurled knob 98is mounted on the upper end portion of the lead screw 60 and providesfor manually rotating the lead screw and shifting the position of thegripper 50 when the pin 90 is in engagement with the lead screw.

Referring to FIGS. 2 and 3, a flat support member or bracket 102 ismounted on a flat surface 103 of the housing portion 22 and projectsforwardly to support a bearing block 104. An elongated screw 105 isrotatably supported by the bearing block 104, and a knob 106 is securedto the forward end portion of the screw 105. An actuating member 108 hasa threaded hole for receiving the screw 105 and it is positioned forengaging the finger 72 of the one-way clutch 65 when the carriage 25 iscompleting its return stroke to pivot the finger 72 and rotate the leadscrew 60 in the direction of the arrow (FIG. 3

A scale 110 is marked on the bracket 102 adjacent a pointer 111 on theactuating member 108 and is calibrated to indicate the extent of lateralmovement of the meat gripper 50 during each return stroke of thecarriage 25. Thus when the actuating member 108 is moved forwardly inrelation to the housing 12, the rotation of the lead screw 60 duringeach return stroke of the carriage is reduced, and when the actuatingmember 108 is moved rearwardly, the rotation of the lead screw 60 isincreased.

ln operation, when a cooked or uncooked piece of meat M (FIG. 1) is tobe shredded or sliced into very thin slices of uniform thickness, as forexample, a thickness of one thirtysecond inch, the meat M is placed onthe inclined surface 34 of the meat tray 30, and the prongs 56 and 58are inserted into the meat. The carriage drive is actuated so that thecarriage 25 reciprocates through a feed stroke and a return stroke inrelation to the rotary knife 15. As mentioned above, when the carriage25 is completing its forward return stroke, the depending finger 72 ofthe one-way clutch 65 engages the actuating member 108 causing the leadscrew 60 to rotate through a predetermined angle and the meat gripper 50to advance toward the gauge plate 42 a predetermined distance accordingto the desired thickness of the slice. When the carriage 25 begins itsrearward feed stroke, the finger 72 and the sleeve 68 of the one-wayclutch 65 return to their home or normal position (FIG. 3) under thebias of the torsion spring 74, but the lead screw 60 is prevented fromrotating backwards by the one-way clutch 80.

From the drawings and the above description, it is apparent that aslicing machine constructed in accordance with the invention providesdesirable features and advantages. For example, the combination of theinclined meat supporting surface 34 and the positive advancement of themeat engaging member or gripper 50 by indexing of the lead screw 60assures that the meat or material will be converted into slices ofprecisely uniform thickness. Furthermore, the mechanism which supportsand advances the meat engaging member 50 is simplified in constructionand is removable with the carriage tray 30 so that the mechanism can beconveniently washed with the tray.

The cooperation between the one-way clutches 65 and also assures thatthe lead screw 60 is positively indexed through a precise predeterminedangle so that the meat gripper 50 is advanced laterally in preciseincremental steps corresponding to the desired thickness of the slices.Moreover, by calibrating the scale with the scale on the knob 45, theoperator of the slicing machine can conveniently set the plate 42according to the incremental advancement of the meat gripper 50 toassure that each slice has a precise unifonn thickness. Furthermore, theconstruction of the meat gripper 50 also provides a desirable feature.That is, the depending prongs 56 assure that the meat is positivelyadvanced with the gripper 50, while the plastic tips 58 on the endprongs 57 protect the pointed ends of the prongs 56 and preventscratching of the meat supporting surface 34.

While the form of apparatus herein described constitutes a preferredembodiment of the invention, it is to be understood that the inventionis not limited to this precise form of apparatus, and that changes maybe made therein without departing from the scope and spirit of theinvention.

What is claimed is:

1. An improved slicing machine comprising a base, an inclined circularslicing knife rotatably supported by said base, a carriage having aninclined surface extending substantially parallel to the axis of saidknife and adapted to support material to be sliced, means supportingsaid carriage for reciprocating movement of said surface adjacent saidknife through a feed stroke and a return stroke, an inclined guide rodmounted on said carriage and extending substantially parallel to saidsurface, a gripping member having a plurality of prongs adapted toengage the material on said surface, an arm pivotally and slidablymounted on said guide rod and supporting said gripping member forlateral movement relative to said surface, an inclined elongated leadscrew mounted on said carriage and extending generally parallel to saidguide rod, means slidably mounted on said guide rod with said am andengaging said lead screw to effect lateral movement of said grippingmember and movement of the material downwardly on said surface inresponse to rotation of said screw, and means for indexing said leadscrew in response to movement of said carriage for producing slices ofprecisely uniform thickness.

2. A slicing machine as defined in claim 1 in combination with aninclined gauge member positioned substantially parallel to said knife,and said gauge member being infinitely movable in relation to said knifefor cooperating with the positive lateral fee of said gripping member toaid in producing slices of precisely uniform thickness.

3. A slicing machine as defined in claim 2 wherein said means forindexing said lead screw is infinitely adjustable between predeterminedlimits, and calibration means for correlating the position of said gaugemember with the lateral advancement of said gripping member.

4. A slicing machine as defined in claim 1 wherein said means forindexing said screw include a one-way clutch connected to the lower endof said screw, a second one-way clutch connecting the upper end of saidlead screw to said carriage, and an adjustable stop member mounted onsaid base and cooperating with said first said one-way clutch to effectpredetermined indexing of said lead screw.

5. A slicing machine as defined in claim 1 including means forreleasably securing said carriage to the corresponding said supportingmeans, and said guide rod, said screw and said 7. A slicing machine asdefined in claim 1 wherein said screw is positioned below said guiderod, means connected to the upper end portion of said guide rod androtatably supporting said screw, and said carriage including means forsupporting the lower end portions of said guide rod and said screw.

8. A slicing machine as defined in claim 1 wherein at least one of saidprongs comprise a plastic member for engaging said surface of saidcarriage to protect said surface.

1. An improved slicing machine comprising a base, an inclined circularslicing knife rotatably supported by said base, a carriage having aninclined surface extending substantially parallel to the axis of saidknife and adapted to support material to be sliced, means supportingsaid carriage for reciprocating movement of said surface adjacent saidknife through a feed stroke and a return stroke, an inclined guide rodmounted on said carriage and extending substantially parallel to saidsurface, a gripping member having a plurality of prongs adapted toengage the material on said surface, an arm pivotally and slidablymounted on said guide rod and supporting said gripping member forlateral movement relative to said surface, an inclined elongated leadscrew mounted on said carriage and extending generally parallel to saidguide rod, means slidably mounted on said guide rod with said arm andengaging said lead screw to effect lateral movement of said grippingmember and movement of the material downwardly on said surface inresponse to rotation of said screw, and means for indexing said leadscrew in response to movement of said carriage for producing slices ofprecisely uniform thickness.
 2. A slicing machine as defined in claim 1in combination with an inclined gauge member positioned substantiallyparallel to said knife, and said gauge member being infinitely movablein relation to said knife for cooperating with the positive lateral feeof said gripping member to aid in producing slices of precisely uniformthickness.
 3. A slicing machine as defined in claim 2 wherein said meansfor indexing said lead screw is infinitely adjustable betweenpredetermined limits, and calibration means for correlating the positionof said gauge member with the lateral advancement of said grippingmember.
 4. A slicing machine as defined in claim 1 wherein said meansfor indexing said screw include a one-way clutch connected to the lowerend of said screw, a second one-way clutch connecting the upper end ofsaid lead screw to said carriage, and an adjustable stop member mountedon said base and cooperating with said first said one-way clutch toeffect predetermined indexing of said lead screw.
 5. A slicing machineas defined in claim 1 including means for releasably securing saidcarriage to the corresponding said supporting means, and said guide rod,said screw and said gripping member all being removable with saidcarriage to facilitate cleaning thereof.
 6. A slicing machine as definedin claim 1 including pivot means connecting said gripping member to saidarm, said means engaging said screw comprise a yoke member includingparallel spaced ears slidably mounted on said guide rod with said armlocated therebetween, and a spring biased retractable plunger mounted onsaid yoke member and releasably engaging said screw to provide forlateral movement of said gripping member without rotating said screw. 7.A slicing machine as defined in claim 1 wherein said screw is positionedbelow said guide rod, means connected to the upper end portion of saidguide rod and rotatably supporting said screw, and said carriageincluding means for supporting the lower end portions of said guide rodand said screw.
 8. A slicing machine as defined in claim 1 wherein atleast one of said prongs comprise a plastic member for engaging saidsurface of said carriage to protect said surface.